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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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#include <linux/bug.h>#include <linux/err.h>#include <linux/export.h>#include <linux/hex.h>#include <linux/minmax.h>#include <linux/printk.h>#include <linux/seq_buf.h>#include <linux/seq_file.h>#include <linux/sprintf.h>#include <linux/string.h>#include <linux/types.h>#include <linux/uaccess.h>
/** * seq_buf_can_fit - can the new data fit in the current buffer? * @s: the seq_buf descriptor * @len: The length to see if it can fit in the current buffer * * Returns: true if there's enough unused space in the seq_buf buffer * to fit the amount of new data according to @len. */static bool seq_buf_can_fit(struct seq_buf *s, size_t len){ return s->len + len <= s->size;}
/** * seq_buf_print_seq - move the contents of seq_buf into a seq_file * @m: the seq_file descriptor that is the destination * @s: the seq_buf descriptor that is the source. * * Returns: zero on success, non-zero otherwise. */int seq_buf_print_seq(struct seq_file *m, struct seq_buf *s){ unsigned int len = seq_buf_used(s);
return seq_write(m, s->buffer, len);}
/** * seq_buf_vprintf - sequence printing of information. * @s: seq_buf descriptor * @fmt: printf format string * @args: va_list of arguments from a printf() type function * * Writes a vnprintf() format into the sequence buffer. * * Returns: zero on success, -1 on overflow. */int seq_buf_vprintf(struct seq_buf *s, const char *fmt, va_list args){ int len;
WARN_ON(s->size == 0);
if (s->len < s->size) { len = vsnprintf(s->buffer + s->len, s->size - s->len, fmt, args); if (s->len + len < s->size) { s->len += len; return 0; } /* vsnprintf() wrote as much as fits, so none of it is stale */ s->len = s->size; } seq_buf_set_overflow(s); return -1;}
/** * seq_buf_printf - sequence printing of information * @s: seq_buf descriptor * @fmt: printf format string * * Writes a printf() format into the sequence buffer. * * Returns: zero on success, -1 on overflow. */int seq_buf_printf(struct seq_buf *s, const char *fmt, ...){ va_list ap; int ret;
va_start(ap, fmt); ret = seq_buf_vprintf(s, fmt, ap); va_end(ap);
return ret;}EXPORT_SYMBOL_GPL(seq_buf_printf);
/** * seq_buf_do_printk - printk() seq_buf line by line * @s: seq_buf descriptor * @lvl: printk level * * printk()-s a multi-line sequential buffer line by line. The function * makes sure that the buffer in @s is NUL-terminated and safe to read * as a string. */void seq_buf_do_printk(struct seq_buf *s, const char *lvl){ const char *start, *lf;
if (s->size == 0 || s->len == 0) return;
start = seq_buf_str(s); while ((lf = strchr(start, '\n'))) { int len = lf - start + 1;
printk("%s%.*s", lvl, len, start); start = ++lf; }
/* No trailing LF */ if (*start) printk("%s%s\n", lvl, start);}EXPORT_SYMBOL_GPL(seq_buf_do_printk);
#ifdef CONFIG_BINARY_PRINTF/** * seq_buf_bprintf - Write the printf string from binary arguments * @s: seq_buf descriptor * @fmt: The format string for the @binary arguments * @binary: The binary arguments for @fmt. * * When recording in a fast path, a printf may be recorded with just * saving the format and the arguments as they were passed to the * function, instead of wasting cycles converting the arguments into * ASCII characters. Instead, the arguments are saved in a 32 bit * word array that is defined by the format string constraints. * * This function will take the format and the binary array and finish * the conversion into the ASCII string within the buffer. * * Returns: zero on success, -1 on overflow. */int seq_buf_bprintf(struct seq_buf *s, const char *fmt, const u32 *binary){ unsigned int len = seq_buf_buffer_left(s); int ret;
WARN_ON(s->size == 0);
if (s->len < s->size) { ret = bstr_printf(s->buffer + s->len, len, fmt, binary); if (s->len + ret < s->size) { s->len += ret; return 0; } /* bstr_printf() wrote as much as fits, so none of it is stale */ s->len = s->size; } seq_buf_set_overflow(s); return -1;}#endif /* CONFIG_BINARY_PRINTF */
/** * seq_buf_puts - sequence printing of simple string * @s: seq_buf descriptor * @str: simple string to record * * Copy a simple string into the sequence buffer. If @str does not fit, * as much of it as fits is copied, followed by a null byte, as * seq_buf_printf() does. * * Returns: zero on success, -1 on overflow. */int seq_buf_puts(struct seq_buf *s, const char *str){ size_t len = strlen(str);
WARN_ON(s->size == 0);
/* Add 1 to len for the trailing null byte which must be there */ len += 1;
if (seq_buf_can_fit(s, len)) { memcpy(s->buffer + s->len, str, len); /* Don't count the trailing null byte against the capacity */ s->len += len - 1; return 0; } /* Copy what fits, so the buffer never holds stale bytes */ if (s->len < s->size) { strscpy(s->buffer + s->len, str, s->size - s->len); s->len = s->size; } seq_buf_set_overflow(s); return -1;}EXPORT_SYMBOL_GPL(seq_buf_puts);
/** * seq_buf_putc - sequence printing of simple character * @s: seq_buf descriptor * @c: simple character to record * * Copy a single character into the sequence buffer. * * Returns: zero on success, -1 on overflow. */int seq_buf_putc(struct seq_buf *s, unsigned char c){ WARN_ON(s->size == 0);
if (seq_buf_can_fit(s, 1)) { s->buffer[s->len++] = c; return 0; } seq_buf_set_overflow(s); return -1;}EXPORT_SYMBOL_GPL(seq_buf_putc);
/** * seq_buf_putmem - write raw data into the sequence buffer * @s: seq_buf descriptor * @mem: The raw memory to copy into the buffer * @len: The length of the raw memory to copy (in bytes) * * There may be cases where raw memory needs to be written into the * buffer and a strcpy() would not work. Using this function allows * for such cases. If @mem does not fit, as much of it as fits is copied. * * Returns: zero on success, -1 on overflow. */int seq_buf_putmem(struct seq_buf *s, const void *mem, unsigned int len){ WARN_ON(s->size == 0);
if (seq_buf_can_fit(s, len)) { memcpy(s->buffer + s->len, mem, len); s->len += len; return 0; } /* Copy what fits, so the buffer never holds stale bytes */ if (s->len < s->size) { memcpy(s->buffer + s->len, mem, s->size - s->len); s->len = s->size; } seq_buf_set_overflow(s); return -1;}EXPORT_SYMBOL_GPL(seq_buf_putmem);
#define MAX_MEMHEX_BYTES 8U#define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1)
/** * seq_buf_putmem_hex - write raw memory into the buffer in ASCII hex * @s: seq_buf descriptor * @mem: The raw memory to write its hex ASCII representation of * @len: The length of the raw memory to copy (in bytes) * * This is similar to seq_buf_putmem() except instead of just copying the * raw memory into the buffer it writes its ASCII representation of it * in hex characters. * * Returns: zero on success, -1 on overflow. */int seq_buf_putmem_hex(struct seq_buf *s, const void *mem, unsigned int len){ unsigned char hex[HEX_CHARS]; const unsigned char *data = mem; unsigned int start_len; int i, j;
WARN_ON(s->size == 0);
BUILD_BUG_ON(MAX_MEMHEX_BYTES * 2 >= HEX_CHARS);
while (len) { start_len = min(len, MAX_MEMHEX_BYTES);#ifdef __BIG_ENDIAN for (i = 0, j = 0; i < start_len; i++) {#else for (i = start_len-1, j = 0; i >= 0; i--) {#endif hex[j++] = hex_asc_hi(data[i]); hex[j++] = hex_asc_lo(data[i]); } if (WARN_ON_ONCE(j == 0 || j/2 > len)) break;
/* j increments twice per loop */ hex[j++] = ' ';
seq_buf_putmem(s, hex, j); if (seq_buf_has_overflowed(s)) return -1;
len -= start_len; data += start_len; } return 0;}EXPORT_SYMBOL_GPL(seq_buf_putmem_hex);
/** * seq_buf_path - copy a path into the sequence buffer * @s: seq_buf descriptor * @path: path to write into the sequence buffer. * @esc: set of characters to escape in the output * * Write a path name into the sequence buffer. * * Returns: the number of written bytes on success, -1 on overflow. */int seq_buf_path(struct seq_buf *s, const struct path *path, const char *esc){ char *buf; size_t size = seq_buf_get_buf(s, &buf); int res = -1;
WARN_ON(s->size == 0);
if (size) { char *p = d_path(path, buf, size); if (!IS_ERR(p)) { char *end = seq_mangle_path(buf, p, esc); if (end) res = end - buf; } } seq_buf_commit(s, res);
return res;}EXPORT_SYMBOL_GPL(seq_buf_path);
/** * seq_buf_to_user - copy the sequence buffer to user space * @s: seq_buf descriptor * @ubuf: The userspace memory location to copy to * @start: The first byte in the buffer to copy * @cnt: The amount to copy * * Copies the sequence buffer into the userspace memory pointed to * by @ubuf. It starts from @start and writes up to @cnt characters * or until it reaches the end of the content in the buffer (@s->len), * whichever comes first. * * Returns: * On success, it returns a positive number of the number of bytes * it copied. * * On failure it returns -EBUSY if all of the content in the * sequence has been already read, which includes nothing in the * sequence (@s->len == @start). * * Returns -EFAULT if the copy to userspace fails. */int seq_buf_to_user(struct seq_buf *s, char __user *ubuf, size_t start, int cnt){ int len; int ret;
if (!cnt) return 0;
len = seq_buf_used(s);
if (len <= start) return -EBUSY;
len -= start; if (cnt > len) cnt = len; ret = copy_to_user(ubuf, s->buffer + start, cnt); if (ret == cnt) return -EFAULT;
return cnt - ret;}
/** * seq_buf_hex_dump - print formatted hex dump into the sequence buffer * @s: seq_buf descriptor * @prefix_str: string to prefix each line with; * caller supplies trailing spaces for alignment if desired * @prefix_type: controls whether prefix of an offset, address, or none * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE) * @rowsize: number of bytes to print per line; must be 16 or 32 * @groupsize: number of bytes to print at a time (1, 2, 4, 8; default = 1) * @buf: data blob to dump * @len: number of bytes in the @buf * @ascii: include ASCII after the hex output * * Function is an analogue of print_hex_dump() and thus has similar interface. * * linebuf size is maximal length for one line:: * * 32 * 3 - maximum bytes per line, each printed into 2 chars + 1 for * separating space * 2 - spaces separating hex dump and ASCII representation * 32 - ASCII representation * 1 - terminating '\0' * * Returns: zero on success, -1 on overflow. */int seq_buf_hex_dump(struct seq_buf *s, const char *prefix_str, int prefix_type, int rowsize, int groupsize, const void *buf, size_t len, bool ascii){ const u8 *ptr = buf; int i, linelen, remaining = len; unsigned char linebuf[32 * 3 + 2 + 32 + 1]; int ret;
if (rowsize != 16 && rowsize != 32) rowsize = 16;
for (i = 0; i < len; i += rowsize) { linelen = min(remaining, rowsize); remaining -= rowsize;
hex_dump_to_buffer(ptr + i, linelen, rowsize, groupsize, linebuf, sizeof(linebuf), ascii);
switch (prefix_type) { case DUMP_PREFIX_ADDRESS: ret = seq_buf_printf(s, "%s%p: %s\n", prefix_str, ptr + i, linebuf); break; case DUMP_PREFIX_OFFSET: ret = seq_buf_printf(s, "%s%.8x: %s\n", prefix_str, i, linebuf); break; default: ret = seq_buf_printf(s, "%s%s\n", prefix_str, linebuf); break; } if (ret) return ret; } return 0;}